1. Field of the Invention
The invention relates in general to folding frames. More particularly, this invention relates to a folding frame that can be conveniently opened for use with four vertical legs and multiple shelves. The folding frame can be collapsed through a simple procedure to a compact format.
2. Description of the Related Art
Inexpensive foldable furniture has been quite popular for numerous years. Foldable furniture (or folding frames) are pieces of furniture that can be expanded for typical use and collapsed for storage or shipping. A few examples of folding frames include folding kitchen islands, serving carts, workbenches, drafting tables, craft tables, gardening carts, and storage shelves.
Although traditional folding frames can collapse to a certain extent, the folded profile of a traditional frame still tends to be bulky. Even in the collapsed format, traditional folding frames take up more room than necessary.
Instead of creating folding frames, some companies ship products in ready-to-assemble packages. This method allows furniture products to be shipped in a compact format, but requires assembly by the end user and does not allow for compact storage.
Thus, the need arises for a preassembled folding frame that can be stored and shipped in a compact format, and can be extended to a full-size piece of furniture such as a table or cart with multiple shelves. In addition, it is desirable that the procedure for transitioning between the collapsed position and the extended position be simple.
In U.S. Pat. No. 6,123,207, Mast discloses a shipping rack easily convertible to an extended mode for storing and shipping product, a display mode for displaying product, and a collapsed mode for storing the rack itself. The rack includes a pair of central support columns and a pair of outer posts on either side of the columns. A plurality of shelves is pivotally mounted between the posts and columns. In the extended mode, the shelves are horizontal. As the columns are raised with respect to the posts, the shelves pivot to the desired inclination. Once the shelves are essentially vertical and the posts are drawn close to the central columns, the rack is in the collapsed mode. The rack can be secured in any mode by a strut. A spring counterbalance system installed within one of the central columns assists the mode conversion of the rack.
Instead of supporting the shelves by using a central support column, the subject invention uses support beams running in a horizontal direction to support the shelves. As the folding frame is transitioned into a collapsed position, the support beams of the subject invention fold horizontally inward. Mast does not describe the use of inward folding support beams.
In U.S. Pat. No. 5,131,547, Goldberg discloses a collapsible storage rack assembly including a plurality of upstanding, generally inverted U-shaped frame members between which extend a plurality of vertically spaced, hingedly collapsible shelf assemblies. Using crossbeams for frame support and foldable movement, the storage rack can be easily and quickly opened for use by moving the frame members away from each other. In a similar manner, the storage rack can be easily collapsed by moving the frame members toward each other and into juxtaposition, with the shelf assemblies collapsing by upward hinging movement. In the closed and collapsed position, the shelf assemblies are substantially completely nested within the frame members, thereby facilitating convenient handling, shipment, and storage of the construction.
Instead of using cross-braces to allow for collapsing of the frame, the subject invention employs support beams that fold horizontally inward. The support beams of the subject invention also function to support the weight of the foldable shelves in the extended position. Goldberg does not describe the use of inward folding support beams to support the shelves.